From: Arnd Bergmann <arnd@arndb.de>
To: Phillip Lougher <phillip@lougher.demon.co.uk>
Subject: Re: [RFC 0/7] [RFC] cramfs: fake write support
Date: Sun, 1 Jun 2008 10:52:03 +0200
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Cc: David Newall <davidn@davidnewall.com>, linux-fsdevel@vger.kernel.org,
       linux-kernel@vger.kernel.org, hch@lst.de
References: <200805311737.58991.arnd@arndb.de> <200805312240.50720.arnd@arndb.de> <48421D65.8040301@lougher.demon.co.uk>
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On Sunday 01 June 2008, Phillip Lougher wrote:
> If I read the patches correctly, when a file page is written to, only 
> that page gets copied into the page cache and locked, the other pages 
> continue to be read off disk from cramfs? ?With Unionfs a page write 
> causes the entire file to be copied up to the r/w tmpfs and locked into 
> the page cache causing unnecessary RAM overhead.

Yes, that's right.

	Arnd <><
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